vsprintf.c 73.7 KB
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/*
 *  linux/lib/vsprintf.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

/* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
/*
 * Wirzenius wrote this portably, Torvalds fucked it up :-)
 */

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/*
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 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
 * - changed to provide snprintf and vsnprintf functions
 * So Feb  1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
 * - scnprintf and vscnprintf
 */

#include <stdarg.h>
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#include <linux/clk.h>
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#include <linux/clk-provider.h>
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#include <linux/module.h>	/* for KSYM_SYMBOL_LEN */
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#include <linux/types.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/kernel.h>
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#include <linux/kallsyms.h>
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#include <linux/math64.h>
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#include <linux/uaccess.h>
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#include <linux/ioport.h>
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#include <linux/dcache.h>
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#include <linux/cred.h>
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#include <linux/uuid.h>
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#include <linux/of.h>
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#include <net/addrconf.h>
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#include <linux/siphash.h>
#include <linux/compiler.h>
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#ifdef CONFIG_BLOCK
#include <linux/blkdev.h>
#endif
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#include "../mm/internal.h"	/* For the trace_print_flags arrays */

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#include <asm/page.h>		/* for PAGE_SIZE */
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#include <asm/byteorder.h>	/* cpu_to_le16 */
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#include <linux/string_helpers.h>
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#include "kstrtox.h"
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/**
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 * simple_strtoull - convert a string to an unsigned long long
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 * @cp: The start of the string
 * @endp: A pointer to the end of the parsed string will be placed here
 * @base: The number base to use
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 *
 * This function is obsolete. Please use kstrtoull instead.
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 */
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unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
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{
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	unsigned long long result;
	unsigned int rv;
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	cp = _parse_integer_fixup_radix(cp, &base);
	rv = _parse_integer(cp, base, &result);
	/* FIXME */
	cp += (rv & ~KSTRTOX_OVERFLOW);
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	if (endp)
		*endp = (char *)cp;
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	return result;
}
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EXPORT_SYMBOL(simple_strtoull);
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/**
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 * simple_strtoul - convert a string to an unsigned long
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 * @cp: The start of the string
 * @endp: A pointer to the end of the parsed string will be placed here
 * @base: The number base to use
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 *
 * This function is obsolete. Please use kstrtoul instead.
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 */
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unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
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{
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	return simple_strtoull(cp, endp, base);
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}
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EXPORT_SYMBOL(simple_strtoul);
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/**
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 * simple_strtol - convert a string to a signed long
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 * @cp: The start of the string
 * @endp: A pointer to the end of the parsed string will be placed here
 * @base: The number base to use
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 *
 * This function is obsolete. Please use kstrtol instead.
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 */
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long simple_strtol(const char *cp, char **endp, unsigned int base)
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{
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	if (*cp == '-')
		return -simple_strtoul(cp + 1, endp, base);
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	return simple_strtoul(cp, endp, base);
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}
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EXPORT_SYMBOL(simple_strtol);
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/**
 * simple_strtoll - convert a string to a signed long long
 * @cp: The start of the string
 * @endp: A pointer to the end of the parsed string will be placed here
 * @base: The number base to use
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 *
 * This function is obsolete. Please use kstrtoll instead.
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 */
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long long simple_strtoll(const char *cp, char **endp, unsigned int base)
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{
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	if (*cp == '-')
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		return -simple_strtoull(cp + 1, endp, base);
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	return simple_strtoull(cp, endp, base);
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}
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EXPORT_SYMBOL(simple_strtoll);
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static noinline_for_stack
int skip_atoi(const char **s)
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{
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	int i = 0;
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	do {
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		i = i*10 + *((*s)++) - '0';
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	} while (isdigit(**s));
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	return i;
}

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/*
 * Decimal conversion is by far the most typical, and is used for
 * /proc and /sys data. This directly impacts e.g. top performance
 * with many processes running. We optimize it for speed by emitting
 * two characters at a time, using a 200 byte lookup table. This
 * roughly halves the number of multiplications compared to computing
 * the digits one at a time. Implementation strongly inspired by the
 * previous version, which in turn used ideas described at
 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
 * from the author, Douglas W. Jones).
 *
 * It turns out there is precisely one 26 bit fixed-point
 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
 * range happens to be somewhat larger (x <= 1073741898), but that's
 * irrelevant for our purpose.
 *
 * For dividing a number in the range [10^4, 10^6-1] by 100, we still
 * need a 32x32->64 bit multiply, so we simply use the same constant.
 *
 * For dividing a number in the range [100, 10^4-1] by 100, there are
 * several options. The simplest is (x * 0x147b) >> 19, which is valid
 * for all x <= 43698.
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 */
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static const u16 decpair[100] = {
#define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
	_( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
	_(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
	_(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
	_(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
	_(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
	_(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
	_(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
	_(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
	_(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
	_(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
#undef _
};

/*
 * This will print a single '0' even if r == 0, since we would
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 * immediately jump to out_r where two 0s would be written but only
 * one of them accounted for in buf. This is needed by ip4_string
 * below. All other callers pass a non-zero value of r.
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*/
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static noinline_for_stack
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char *put_dec_trunc8(char *buf, unsigned r)
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{
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	unsigned q;

	/* 1 <= r < 10^8 */
	if (r < 100)
		goto out_r;

	/* 100 <= r < 10^8 */
	q = (r * (u64)0x28f5c29) >> 32;
	*((u16 *)buf) = decpair[r - 100*q];
	buf += 2;

	/* 1 <= q < 10^6 */
	if (q < 100)
		goto out_q;

	/*  100 <= q < 10^6 */
	r = (q * (u64)0x28f5c29) >> 32;
	*((u16 *)buf) = decpair[q - 100*r];
	buf += 2;

	/* 1 <= r < 10^4 */
	if (r < 100)
		goto out_r;

	/* 100 <= r < 10^4 */
	q = (r * 0x147b) >> 19;
	*((u16 *)buf) = decpair[r - 100*q];
	buf += 2;
out_q:
	/* 1 <= q < 100 */
	r = q;
out_r:
	/* 1 <= r < 100 */
	*((u16 *)buf) = decpair[r];
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	buf += r < 10 ? 1 : 2;
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	return buf;
}
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#if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
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static noinline_for_stack
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char *put_dec_full8(char *buf, unsigned r)
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{
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	unsigned q;

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	/* 0 <= r < 10^8 */
	q = (r * (u64)0x28f5c29) >> 32;
	*((u16 *)buf) = decpair[r - 100*q];
	buf += 2;
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	/* 0 <= q < 10^6 */
	r = (q * (u64)0x28f5c29) >> 32;
	*((u16 *)buf) = decpair[q - 100*r];
	buf += 2;
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	/* 0 <= r < 10^4 */
	q = (r * 0x147b) >> 19;
	*((u16 *)buf) = decpair[r - 100*q];
	buf += 2;
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	/* 0 <= q < 100 */
	*((u16 *)buf) = decpair[q];
	buf += 2;
	return buf;
}
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static noinline_for_stack
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char *put_dec(char *buf, unsigned long long n)
{
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	if (n >= 100*1000*1000)
		buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
	/* 1 <= n <= 1.6e11 */
	if (n >= 100*1000*1000)
		buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
	/* 1 <= n < 1e8 */
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	return put_dec_trunc8(buf, n);
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}
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#elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
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static void
put_dec_full4(char *buf, unsigned r)
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{
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	unsigned q;

	/* 0 <= r < 10^4 */
	q = (r * 0x147b) >> 19;
	*((u16 *)buf) = decpair[r - 100*q];
	buf += 2;
	/* 0 <= q < 100 */
	*((u16 *)buf) = decpair[q];
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}

/*
 * Call put_dec_full4 on x % 10000, return x / 10000.
 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
 * holds for all x < 1,128,869,999.  The largest value this
 * helper will ever be asked to convert is 1,125,520,955.
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 * (second call in the put_dec code, assuming n is all-ones).
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 */
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static noinline_for_stack
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unsigned put_dec_helper4(char *buf, unsigned x)
{
        uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;

        put_dec_full4(buf, x - q * 10000);
        return q;
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}

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/* Based on code by Douglas W. Jones found at
 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
 * (with permission from the author).
 * Performs no 64-bit division and hence should be fast on 32-bit machines.
 */
static
char *put_dec(char *buf, unsigned long long n)
{
	uint32_t d3, d2, d1, q, h;

	if (n < 100*1000*1000)
		return put_dec_trunc8(buf, n);

	d1  = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
	h   = (n >> 32);
	d2  = (h      ) & 0xffff;
	d3  = (h >> 16); /* implicit "& 0xffff" */

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	/* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
	     = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
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	q   = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
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	q = put_dec_helper4(buf, q);

	q += 7671 * d3 + 9496 * d2 + 6 * d1;
	q = put_dec_helper4(buf+4, q);

	q += 4749 * d3 + 42 * d2;
	q = put_dec_helper4(buf+8, q);
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	q += 281 * d3;
	buf += 12;
	if (q)
		buf = put_dec_trunc8(buf, q);
	else while (buf[-1] == '0')
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		--buf;

	return buf;
}

#endif

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/*
 * Convert passed number to decimal string.
 * Returns the length of string.  On buffer overflow, returns 0.
 *
 * If speed is not important, use snprintf(). It's easy to read the code.
 */
int num_to_str(char *buf, int size, unsigned long long num)
{
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	/* put_dec requires 2-byte alignment of the buffer. */
	char tmp[sizeof(num) * 3] __aligned(2);
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	int idx, len;

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	/* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
	if (num <= 9) {
		tmp[0] = '0' + num;
		len = 1;
	} else {
		len = put_dec(tmp, num) - tmp;
	}
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	if (len > size)
		return 0;
	for (idx = 0; idx < len; ++idx)
		buf[idx] = tmp[len - idx - 1];
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	return len;
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}

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#define SIGN	1		/* unsigned/signed, must be 1 */
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#define LEFT	2		/* left justified */
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#define PLUS	4		/* show plus */
#define SPACE	8		/* space if plus */
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#define ZEROPAD	16		/* pad with zero, must be 16 == '0' - ' ' */
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#define SMALL	32		/* use lowercase in hex (must be 32 == 0x20) */
#define SPECIAL	64		/* prefix hex with "0x", octal with "0" */
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enum format_type {
	FORMAT_TYPE_NONE, /* Just a string part */
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	FORMAT_TYPE_WIDTH,
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	FORMAT_TYPE_PRECISION,
	FORMAT_TYPE_CHAR,
	FORMAT_TYPE_STR,
	FORMAT_TYPE_PTR,
	FORMAT_TYPE_PERCENT_CHAR,
	FORMAT_TYPE_INVALID,
	FORMAT_TYPE_LONG_LONG,
	FORMAT_TYPE_ULONG,
	FORMAT_TYPE_LONG,
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	FORMAT_TYPE_UBYTE,
	FORMAT_TYPE_BYTE,
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	FORMAT_TYPE_USHORT,
	FORMAT_TYPE_SHORT,
	FORMAT_TYPE_UINT,
	FORMAT_TYPE_INT,
	FORMAT_TYPE_SIZE_T,
	FORMAT_TYPE_PTRDIFF
};

struct printf_spec {
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	unsigned int	type:8;		/* format_type enum */
	signed int	field_width:24;	/* width of output field */
	unsigned int	flags:8;	/* flags to number() */
	unsigned int	base:8;		/* number base, 8, 10 or 16 only */
	signed int	precision:16;	/* # of digits/chars */
} __packed;
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#define FIELD_WIDTH_MAX ((1 << 23) - 1)
#define PRECISION_MAX ((1 << 15) - 1)
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static noinline_for_stack
char *number(char *buf, char *end, unsigned long long num,
	     struct printf_spec spec)
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{
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	/* put_dec requires 2-byte alignment of the buffer. */
	char tmp[3 * sizeof(num)] __aligned(2);
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	char sign;
	char locase;
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	int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
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	int i;
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	bool is_zero = num == 0LL;
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	int field_width = spec.field_width;
	int precision = spec.precision;
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	BUILD_BUG_ON(sizeof(struct printf_spec) != 8);

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	/* locase = 0 or 0x20. ORing digits or letters with 'locase'
	 * produces same digits or (maybe lowercased) letters */
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	locase = (spec.flags & SMALL);
	if (spec.flags & LEFT)
		spec.flags &= ~ZEROPAD;
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	sign = 0;
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	if (spec.flags & SIGN) {
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		if ((signed long long)num < 0) {
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			sign = '-';
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			num = -(signed long long)num;
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			field_width--;
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		} else if (spec.flags & PLUS) {
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			sign = '+';
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			field_width--;
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		} else if (spec.flags & SPACE) {
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			sign = ' ';
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			field_width--;
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		}
	}
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	if (need_pfx) {
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		if (spec.base == 16)
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			field_width -= 2;
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		else if (!is_zero)
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			field_width--;
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	}
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	/* generate full string in tmp[], in reverse order */
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	i = 0;
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	if (num < spec.base)
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		tmp[i++] = hex_asc_upper[num] | locase;
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	else if (spec.base != 10) { /* 8 or 16 */
		int mask = spec.base - 1;
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		int shift = 3;
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		if (spec.base == 16)
			shift = 4;
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		do {
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			tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
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			num >>= shift;
		} while (num);
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	} else { /* base 10 */
		i = put_dec(tmp, num) - tmp;
	}
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	/* printing 100 using %2d gives "100", not "00" */
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	if (i > precision)
		precision = i;
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	/* leading space padding */
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	field_width -= precision;
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	if (!(spec.flags & (ZEROPAD | LEFT))) {
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		while (--field_width >= 0) {
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			if (buf < end)
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				*buf = ' ';
			++buf;
		}
	}
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	/* sign */
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	if (sign) {
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		if (buf < end)
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			*buf = sign;
		++buf;
	}
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	/* "0x" / "0" prefix */
	if (need_pfx) {
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		if (spec.base == 16 || !is_zero) {
			if (buf < end)
				*buf = '0';
			++buf;
		}
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		if (spec.base == 16) {
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			if (buf < end)
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				*buf = ('X' | locase);
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			++buf;
		}
	}
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	/* zero or space padding */
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	if (!(spec.flags & LEFT)) {
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		char c = ' ' + (spec.flags & ZEROPAD);
		BUILD_BUG_ON(' ' + ZEROPAD != '0');
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		while (--field_width >= 0) {
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			if (buf < end)
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				*buf = c;
			++buf;
		}
	}
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	/* hmm even more zero padding? */
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	while (i <= --precision) {
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		if (buf < end)
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			*buf = '0';
		++buf;
	}
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	/* actual digits of result */
	while (--i >= 0) {
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		if (buf < end)
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			*buf = tmp[i];
		++buf;
	}
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	/* trailing space padding */
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	while (--field_width >= 0) {
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		if (buf < end)
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			*buf = ' ';
		++buf;
	}
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	return buf;
}

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static noinline_for_stack
char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
{
	struct printf_spec spec;

	spec.type = FORMAT_TYPE_PTR;
	spec.field_width = 2 + 2 * size;	/* 0x + hex */
	spec.flags = SPECIAL | SMALL | ZEROPAD;
	spec.base = 16;
	spec.precision = -1;

	return number(buf, end, num, spec);
}

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static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
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{
	size_t size;
	if (buf >= end)	/* nowhere to put anything */
		return;
	size = end - buf;
	if (size <= spaces) {
		memset(buf, ' ', size);
		return;
	}
	if (len) {
		if (len > size - spaces)
			len = size - spaces;
		memmove(buf + spaces, buf, len);
	}
	memset(buf, ' ', spaces);
}

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/*
 * Handle field width padding for a string.
 * @buf: current buffer position
 * @n: length of string
 * @end: end of output buffer
 * @spec: for field width and flags
 * Returns: new buffer position after padding.
 */
static noinline_for_stack
char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
{
	unsigned spaces;

	if (likely(n >= spec.field_width))
		return buf;
	/* we want to pad the sucker */
	spaces = spec.field_width - n;
	if (!(spec.flags & LEFT)) {
		move_right(buf - n, end, n, spaces);
		return buf + spaces;
	}
	while (spaces--) {
		if (buf < end)
			*buf = ' ';
		++buf;
	}
	return buf;
}

584 585 586
static noinline_for_stack
char *string(char *buf, char *end, const char *s, struct printf_spec spec)
{
587 588
	int len = 0;
	size_t lim = spec.precision;
589 590 591 592

	if ((unsigned long)s < PAGE_SIZE)
		s = "(null)";

593 594 595 596
	while (lim--) {
		char c = *s++;
		if (!c)
			break;
597
		if (buf < end)
598
			*buf = c;
599
		++buf;
600
		++len;
601
	}
602
	return widen_string(buf, len, end, spec);
603 604
}

A
Al Viro 已提交
605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623
static noinline_for_stack
char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
		  const char *fmt)
{
	const char *array[4], *s;
	const struct dentry *p;
	int depth;
	int i, n;

	switch (fmt[1]) {
		case '2': case '3': case '4':
			depth = fmt[1] - '0';
			break;
		default:
			depth = 1;
	}

	rcu_read_lock();
	for (i = 0; i < depth; i++, d = p) {
624 625
		p = READ_ONCE(d->d_parent);
		array[i] = READ_ONCE(d->d_name.name);
A
Al Viro 已提交
626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645
		if (p == d) {
			if (i)
				array[i] = "";
			i++;
			break;
		}
	}
	s = array[--i];
	for (n = 0; n != spec.precision; n++, buf++) {
		char c = *s++;
		if (!c) {
			if (!i)
				break;
			c = '/';
			s = array[--i];
		}
		if (buf < end)
			*buf = c;
	}
	rcu_read_unlock();
646
	return widen_string(buf, n, end, spec);
A
Al Viro 已提交
647 648
}

649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668
#ifdef CONFIG_BLOCK
static noinline_for_stack
char *bdev_name(char *buf, char *end, struct block_device *bdev,
		struct printf_spec spec, const char *fmt)
{
	struct gendisk *hd = bdev->bd_disk;
	
	buf = string(buf, end, hd->disk_name, spec);
	if (bdev->bd_part->partno) {
		if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
			if (buf < end)
				*buf = 'p';
			buf++;
		}
		buf = number(buf, end, bdev->bd_part->partno, spec);
	}
	return buf;
}
#endif

J
Joe Perches 已提交
669 670
static noinline_for_stack
char *symbol_string(char *buf, char *end, void *ptr,
671
		    struct printf_spec spec, const char *fmt)
672
{
673
	unsigned long value;
674 675
#ifdef CONFIG_KALLSYMS
	char sym[KSYM_SYMBOL_LEN];
676 677 678 679 680 681 682 683
#endif

	if (fmt[1] == 'R')
		ptr = __builtin_extract_return_addr(ptr);
	value = (unsigned long)ptr;

#ifdef CONFIG_KALLSYMS
	if (*fmt == 'B')
684
		sprint_backtrace(sym, value);
685
	else if (*fmt != 'f' && *fmt != 's')
686 687
		sprint_symbol(sym, value);
	else
688
		sprint_symbol_no_offset(sym, value);
689

690
	return string(buf, end, sym, spec);
691
#else
692
	return special_hex_number(buf, end, value, sizeof(void *));
693 694 695
#endif
}

696 697 698 699 700
static const struct printf_spec default_str_spec = {
	.field_width = -1,
	.precision = -1,
};

701 702 703 704 705 706
static const struct printf_spec default_flag_spec = {
	.base = 16,
	.precision = -1,
	.flags = SPECIAL | SMALL,
};

707 708 709 710 711
static const struct printf_spec default_dec_spec = {
	.base = 10,
	.precision = -1,
};

J
Joe Perches 已提交
712 713 714
static noinline_for_stack
char *resource_string(char *buf, char *end, struct resource *res,
		      struct printf_spec spec, const char *fmt)
715 716
{
#ifndef IO_RSRC_PRINTK_SIZE
717
#define IO_RSRC_PRINTK_SIZE	6
718 719 720
#endif

#ifndef MEM_RSRC_PRINTK_SIZE
721
#define MEM_RSRC_PRINTK_SIZE	10
722
#endif
723
	static const struct printf_spec io_spec = {
724
		.base = 16,
725
		.field_width = IO_RSRC_PRINTK_SIZE,
726 727 728
		.precision = -1,
		.flags = SPECIAL | SMALL | ZEROPAD,
	};
729 730 731 732 733 734
	static const struct printf_spec mem_spec = {
		.base = 16,
		.field_width = MEM_RSRC_PRINTK_SIZE,
		.precision = -1,
		.flags = SPECIAL | SMALL | ZEROPAD,
	};
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Bjorn Helgaas 已提交
735 736 737 738 739 740
	static const struct printf_spec bus_spec = {
		.base = 16,
		.field_width = 2,
		.precision = -1,
		.flags = SMALL | ZEROPAD,
	};
741
	static const struct printf_spec str_spec = {
742 743 744 745
		.field_width = -1,
		.precision = 10,
		.flags = LEFT,
	};
746 747 748 749 750

	/* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
	 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
#define RSRC_BUF_SIZE		((2 * sizeof(resource_size_t)) + 4)
#define FLAG_BUF_SIZE		(2 * sizeof(res->flags))
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Bjorn Helgaas 已提交
751
#define DECODED_BUF_SIZE	sizeof("[mem - 64bit pref window disabled]")
752 753 754 755
#define RAW_BUF_SIZE		sizeof("[mem - flags 0x]")
	char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
		     2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];

756
	char *p = sym, *pend = sym + sizeof(sym);
757
	int decode = (fmt[0] == 'R') ? 1 : 0;
758
	const struct printf_spec *specp;
759 760

	*p++ = '[';
761
	if (res->flags & IORESOURCE_IO) {
762
		p = string(p, pend, "io  ", str_spec);
763 764
		specp = &io_spec;
	} else if (res->flags & IORESOURCE_MEM) {
765
		p = string(p, pend, "mem ", str_spec);
766 767
		specp = &mem_spec;
	} else if (res->flags & IORESOURCE_IRQ) {
768
		p = string(p, pend, "irq ", str_spec);
769
		specp = &default_dec_spec;
770
	} else if (res->flags & IORESOURCE_DMA) {
771
		p = string(p, pend, "dma ", str_spec);
772
		specp = &default_dec_spec;
B
Bjorn Helgaas 已提交
773 774 775
	} else if (res->flags & IORESOURCE_BUS) {
		p = string(p, pend, "bus ", str_spec);
		specp = &bus_spec;
776
	} else {
777
		p = string(p, pend, "??? ", str_spec);
778
		specp = &mem_spec;
779
		decode = 0;
780
	}
781 782 783 784 785 786 787 788 789
	if (decode && res->flags & IORESOURCE_UNSET) {
		p = string(p, pend, "size ", str_spec);
		p = number(p, pend, resource_size(res), *specp);
	} else {
		p = number(p, pend, res->start, *specp);
		if (res->start != res->end) {
			*p++ = '-';
			p = number(p, pend, res->end, *specp);
		}
790
	}
791
	if (decode) {
792 793 794 795
		if (res->flags & IORESOURCE_MEM_64)
			p = string(p, pend, " 64bit", str_spec);
		if (res->flags & IORESOURCE_PREFETCH)
			p = string(p, pend, " pref", str_spec);
B
Bjorn Helgaas 已提交
796 797
		if (res->flags & IORESOURCE_WINDOW)
			p = string(p, pend, " window", str_spec);
798 799
		if (res->flags & IORESOURCE_DISABLED)
			p = string(p, pend, " disabled", str_spec);
800 801
	} else {
		p = string(p, pend, " flags ", str_spec);
802
		p = number(p, pend, res->flags, default_flag_spec);
803
	}
804
	*p++ = ']';
805
	*p = '\0';
806

807
	return string(buf, end, sym, spec);
808 809
}

810 811 812 813
static noinline_for_stack
char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
		 const char *fmt)
{
814
	int i, len = 1;		/* if we pass '%ph[CDN]', field width remains
815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843
				   negative value, fallback to the default */
	char separator;

	if (spec.field_width == 0)
		/* nothing to print */
		return buf;

	if (ZERO_OR_NULL_PTR(addr))
		/* NULL pointer */
		return string(buf, end, NULL, spec);

	switch (fmt[1]) {
	case 'C':
		separator = ':';
		break;
	case 'D':
		separator = '-';
		break;
	case 'N':
		separator = 0;
		break;
	default:
		separator = ' ';
		break;
	}

	if (spec.field_width > 0)
		len = min_t(int, spec.field_width, 64);

844 845 846 847 848 849 850
	for (i = 0; i < len; ++i) {
		if (buf < end)
			*buf = hex_asc_hi(addr[i]);
		++buf;
		if (buf < end)
			*buf = hex_asc_lo(addr[i]);
		++buf;
851

852 853 854 855 856
		if (separator && i != len - 1) {
			if (buf < end)
				*buf = separator;
			++buf;
		}
857 858 859 860 861
	}

	return buf;
}

862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925
static noinline_for_stack
char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
		    struct printf_spec spec, const char *fmt)
{
	const int CHUNKSZ = 32;
	int nr_bits = max_t(int, spec.field_width, 0);
	int i, chunksz;
	bool first = true;

	/* reused to print numbers */
	spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };

	chunksz = nr_bits & (CHUNKSZ - 1);
	if (chunksz == 0)
		chunksz = CHUNKSZ;

	i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
	for (; i >= 0; i -= CHUNKSZ) {
		u32 chunkmask, val;
		int word, bit;

		chunkmask = ((1ULL << chunksz) - 1);
		word = i / BITS_PER_LONG;
		bit = i % BITS_PER_LONG;
		val = (bitmap[word] >> bit) & chunkmask;

		if (!first) {
			if (buf < end)
				*buf = ',';
			buf++;
		}
		first = false;

		spec.field_width = DIV_ROUND_UP(chunksz, 4);
		buf = number(buf, end, val, spec);

		chunksz = CHUNKSZ;
	}
	return buf;
}

static noinline_for_stack
char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
			 struct printf_spec spec, const char *fmt)
{
	int nr_bits = max_t(int, spec.field_width, 0);
	/* current bit is 'cur', most recently seen range is [rbot, rtop] */
	int cur, rbot, rtop;
	bool first = true;

	rbot = cur = find_first_bit(bitmap, nr_bits);
	while (cur < nr_bits) {
		rtop = cur;
		cur = find_next_bit(bitmap, nr_bits, cur + 1);
		if (cur < nr_bits && cur <= rtop + 1)
			continue;

		if (!first) {
			if (buf < end)
				*buf = ',';
			buf++;
		}
		first = false;

926
		buf = number(buf, end, rbot, default_dec_spec);
927 928 929 930 931
		if (rbot < rtop) {
			if (buf < end)
				*buf = '-';
			buf++;

932
			buf = number(buf, end, rtop, default_dec_spec);
933 934 935 936 937 938 939
		}

		rbot = cur;
	}
	return buf;
}

J
Joe Perches 已提交
940 941 942
static noinline_for_stack
char *mac_address_string(char *buf, char *end, u8 *addr,
			 struct printf_spec spec, const char *fmt)
943
{
944
	char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
945 946
	char *p = mac_addr;
	int i;
947
	char separator;
948
	bool reversed = false;
949

950 951
	switch (fmt[1]) {
	case 'F':
952
		separator = '-';
953 954 955 956 957 958 959
		break;

	case 'R':
		reversed = true;
		/* fall through */

	default:
960
		separator = ':';
961
		break;
962
	}
963 964

	for (i = 0; i < 6; i++) {
965 966 967 968 969
		if (reversed)
			p = hex_byte_pack(p, addr[5 - i]);
		else
			p = hex_byte_pack(p, addr[i]);

970
		if (fmt[0] == 'M' && i != 5)
971
			*p++ = separator;
972 973 974
	}
	*p = '\0';

975
	return string(buf, end, mac_addr, spec);
976 977
}

J
Joe Perches 已提交
978 979
static noinline_for_stack
char *ip4_string(char *p, const u8 *addr, const char *fmt)
980 981
{
	int i;
982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006
	bool leading_zeros = (fmt[0] == 'i');
	int index;
	int step;

	switch (fmt[2]) {
	case 'h':
#ifdef __BIG_ENDIAN
		index = 0;
		step = 1;
#else
		index = 3;
		step = -1;
#endif
		break;
	case 'l':
		index = 3;
		step = -1;
		break;
	case 'n':
	case 'b':
	default:
		index = 0;
		step = 1;
		break;
	}
1007
	for (i = 0; i < 4; i++) {
1008
		char temp[4] __aligned(2);	/* hold each IP quad in reverse order */
1009
		int digits = put_dec_trunc8(temp, addr[index]) - temp;
1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020
		if (leading_zeros) {
			if (digits < 3)
				*p++ = '0';
			if (digits < 2)
				*p++ = '0';
		}
		/* reverse the digits in the quad */
		while (digits--)
			*p++ = temp[digits];
		if (i < 3)
			*p++ = '.';
1021
		index += step;
1022 1023
	}
	*p = '\0';
1024

1025 1026 1027
	return p;
}

J
Joe Perches 已提交
1028 1029
static noinline_for_stack
char *ip6_compressed_string(char *p, const char *addr)
1030
{
1031
	int i, j, range;
1032 1033 1034 1035
	unsigned char zerolength[8];
	int longest = 1;
	int colonpos = -1;
	u16 word;
1036
	u8 hi, lo;
1037
	bool needcolon = false;
1038 1039 1040 1041 1042 1043
	bool useIPv4;
	struct in6_addr in6;

	memcpy(&in6, addr, sizeof(struct in6_addr));

	useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054

	memset(zerolength, 0, sizeof(zerolength));

	if (useIPv4)
		range = 6;
	else
		range = 8;

	/* find position of longest 0 run */
	for (i = 0; i < range; i++) {
		for (j = i; j < range; j++) {
1055
			if (in6.s6_addr16[j] != 0)
1056 1057 1058 1059 1060 1061 1062 1063 1064 1065
				break;
			zerolength[i]++;
		}
	}
	for (i = 0; i < range; i++) {
		if (zerolength[i] > longest) {
			longest = zerolength[i];
			colonpos = i;
		}
	}
1066 1067
	if (longest == 1)		/* don't compress a single 0 */
		colonpos = -1;
1068

1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083
	/* emit address */
	for (i = 0; i < range; i++) {
		if (i == colonpos) {
			if (needcolon || i == 0)
				*p++ = ':';
			*p++ = ':';
			needcolon = false;
			i += longest - 1;
			continue;
		}
		if (needcolon) {
			*p++ = ':';
			needcolon = false;
		}
		/* hex u16 without leading 0s */
1084
		word = ntohs(in6.s6_addr16[i]);
1085 1086 1087 1088
		hi = word >> 8;
		lo = word & 0xff;
		if (hi) {
			if (hi > 0x0f)
1089
				p = hex_byte_pack(p, hi);
1090 1091
			else
				*p++ = hex_asc_lo(hi);
1092
			p = hex_byte_pack(p, lo);
1093
		}
1094
		else if (lo > 0x0f)
1095
			p = hex_byte_pack(p, lo);
1096 1097 1098 1099 1100 1101 1102 1103
		else
			*p++ = hex_asc_lo(lo);
		needcolon = true;
	}

	if (useIPv4) {
		if (needcolon)
			*p++ = ':';
1104
		p = ip4_string(p, &in6.s6_addr[12], "I4");
1105 1106
	}
	*p = '\0';
1107

1108 1109 1110
	return p;
}

J
Joe Perches 已提交
1111 1112
static noinline_for_stack
char *ip6_string(char *p, const char *addr, const char *fmt)
1113 1114
{
	int i;
1115

1116
	for (i = 0; i < 8; i++) {
1117 1118
		p = hex_byte_pack(p, *addr++);
		p = hex_byte_pack(p, *addr++);
1119
		if (fmt[0] == 'I' && i != 7)
1120 1121 1122
			*p++ = ':';
	}
	*p = '\0';
1123

1124 1125 1126
	return p;
}

J
Joe Perches 已提交
1127 1128 1129
static noinline_for_stack
char *ip6_addr_string(char *buf, char *end, const u8 *addr,
		      struct printf_spec spec, const char *fmt)
1130 1131 1132 1133
{
	char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];

	if (fmt[0] == 'I' && fmt[2] == 'c')
1134
		ip6_compressed_string(ip6_addr, addr);
1135
	else
1136
		ip6_string(ip6_addr, addr, fmt);
1137

1138
	return string(buf, end, ip6_addr, spec);
1139 1140
}

J
Joe Perches 已提交
1141 1142 1143
static noinline_for_stack
char *ip4_addr_string(char *buf, char *end, const u8 *addr,
		      struct printf_spec spec, const char *fmt)
1144
{
1145
	char ip4_addr[sizeof("255.255.255.255")];
1146

1147
	ip4_string(ip4_addr, addr, fmt);
1148

1149
	return string(buf, end, ip4_addr, spec);
1150 1151
}

1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248
static noinline_for_stack
char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
			 struct printf_spec spec, const char *fmt)
{
	bool have_p = false, have_s = false, have_f = false, have_c = false;
	char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
		      sizeof(":12345") + sizeof("/123456789") +
		      sizeof("%1234567890")];
	char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
	const u8 *addr = (const u8 *) &sa->sin6_addr;
	char fmt6[2] = { fmt[0], '6' };
	u8 off = 0;

	fmt++;
	while (isalpha(*++fmt)) {
		switch (*fmt) {
		case 'p':
			have_p = true;
			break;
		case 'f':
			have_f = true;
			break;
		case 's':
			have_s = true;
			break;
		case 'c':
			have_c = true;
			break;
		}
	}

	if (have_p || have_s || have_f) {
		*p = '[';
		off = 1;
	}

	if (fmt6[0] == 'I' && have_c)
		p = ip6_compressed_string(ip6_addr + off, addr);
	else
		p = ip6_string(ip6_addr + off, addr, fmt6);

	if (have_p || have_s || have_f)
		*p++ = ']';

	if (have_p) {
		*p++ = ':';
		p = number(p, pend, ntohs(sa->sin6_port), spec);
	}
	if (have_f) {
		*p++ = '/';
		p = number(p, pend, ntohl(sa->sin6_flowinfo &
					  IPV6_FLOWINFO_MASK), spec);
	}
	if (have_s) {
		*p++ = '%';
		p = number(p, pend, sa->sin6_scope_id, spec);
	}
	*p = '\0';

	return string(buf, end, ip6_addr, spec);
}

static noinline_for_stack
char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
			 struct printf_spec spec, const char *fmt)
{
	bool have_p = false;
	char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
	char *pend = ip4_addr + sizeof(ip4_addr);
	const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
	char fmt4[3] = { fmt[0], '4', 0 };

	fmt++;
	while (isalpha(*++fmt)) {
		switch (*fmt) {
		case 'p':
			have_p = true;
			break;
		case 'h':
		case 'l':
		case 'n':
		case 'b':
			fmt4[2] = *fmt;
			break;
		}
	}

	p = ip4_string(ip4_addr, addr, fmt4);
	if (have_p) {
		*p++ = ':';
		p = number(p, pend, ntohs(sa->sin_port), spec);
	}
	*p = '\0';

	return string(buf, end, ip4_addr, spec);
}

1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298
static noinline_for_stack
char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
		     const char *fmt)
{
	bool found = true;
	int count = 1;
	unsigned int flags = 0;
	int len;

	if (spec.field_width == 0)
		return buf;				/* nothing to print */

	if (ZERO_OR_NULL_PTR(addr))
		return string(buf, end, NULL, spec);	/* NULL pointer */


	do {
		switch (fmt[count++]) {
		case 'a':
			flags |= ESCAPE_ANY;
			break;
		case 'c':
			flags |= ESCAPE_SPECIAL;
			break;
		case 'h':
			flags |= ESCAPE_HEX;
			break;
		case 'n':
			flags |= ESCAPE_NULL;
			break;
		case 'o':
			flags |= ESCAPE_OCTAL;
			break;
		case 'p':
			flags |= ESCAPE_NP;
			break;
		case 's':
			flags |= ESCAPE_SPACE;
			break;
		default:
			found = false;
			break;
		}
	} while (found);

	if (!flags)
		flags = ESCAPE_ANY_NP;

	len = spec.field_width < 0 ? 1 : spec.field_width;

1299 1300 1301 1302 1303 1304
	/*
	 * string_escape_mem() writes as many characters as it can to
	 * the given buffer, and returns the total size of the output
	 * had the buffer been big enough.
	 */
	buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1305 1306 1307 1308

	return buf;
}

J
Joe Perches 已提交
1309 1310 1311
static noinline_for_stack
char *uuid_string(char *buf, char *end, const u8 *addr,
		  struct printf_spec spec, const char *fmt)
1312
{
1313
	char uuid[UUID_STRING_LEN + 1];
1314 1315
	char *p = uuid;
	int i;
C
Christoph Hellwig 已提交
1316
	const u8 *index = uuid_index;
1317 1318 1319 1320 1321 1322
	bool uc = false;

	switch (*(++fmt)) {
	case 'L':
		uc = true;		/* fall-through */
	case 'l':
C
Christoph Hellwig 已提交
1323
		index = guid_index;
1324 1325 1326 1327 1328 1329 1330
		break;
	case 'B':
		uc = true;
		break;
	}

	for (i = 0; i < 16; i++) {
1331 1332 1333 1334
		if (uc)
			p = hex_byte_pack_upper(p, addr[index[i]]);
		else
			p = hex_byte_pack(p, addr[index[i]]);
1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349
		switch (i) {
		case 3:
		case 5:
		case 7:
		case 9:
			*p++ = '-';
			break;
		}
	}

	*p = 0;

	return string(buf, end, uuid, spec);
}

1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363
static noinline_for_stack
char *pointer_string(char *buf, char *end, const void *ptr,
		     struct printf_spec spec)
{
	spec.base = 16;
	spec.flags |= SMALL;
	if (spec.field_width == -1) {
		spec.field_width = 2 * sizeof(ptr);
		spec.flags |= ZEROPAD;
	}

	return number(buf, end, (unsigned long int)ptr, spec);
}

1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380
int kptr_restrict __read_mostly;

static noinline_for_stack
char *restricted_pointer(char *buf, char *end, const void *ptr,
			 struct printf_spec spec)
{
	switch (kptr_restrict) {
	case 0:
		/* Always print %pK values */
		break;
	case 1: {
		const struct cred *cred;

		/*
		 * kptr_restrict==1 cannot be used in IRQ context
		 * because its test for CAP_SYSLOG would be meaningless.
		 */
1381 1382 1383
		if (in_irq() || in_serving_softirq() || in_nmi()) {
			if (spec.field_width == -1)
				spec.field_width = 2 * sizeof(ptr);
1384
			return string(buf, end, "pK-error", spec);
1385
		}
1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409

		/*
		 * Only print the real pointer value if the current
		 * process has CAP_SYSLOG and is running with the
		 * same credentials it started with. This is because
		 * access to files is checked at open() time, but %pK
		 * checks permission at read() time. We don't want to
		 * leak pointer values if a binary opens a file using
		 * %pK and then elevates privileges before reading it.
		 */
		cred = current_cred();
		if (!has_capability_noaudit(current, CAP_SYSLOG) ||
		    !uid_eq(cred->euid, cred->uid) ||
		    !gid_eq(cred->egid, cred->gid))
			ptr = NULL;
		break;
	}
	case 2:
	default:
		/* Always print 0's for %pK */
		ptr = NULL;
		break;
	}

1410
	return pointer_string(buf, end, ptr, spec);
1411 1412
}

1413 1414
static noinline_for_stack
char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt)
1415
{
1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428
	unsigned long long num;
	int size;

	switch (fmt[1]) {
	case 'F':
		num = *(const netdev_features_t *)addr;
		size = sizeof(netdev_features_t);
		break;
	default:
		num = (unsigned long)addr;
		size = sizeof(unsigned long);
		break;
	}
1429

1430
	return special_hex_number(buf, end, num, size);
1431 1432
}

1433
static noinline_for_stack
1434
char *address_val(char *buf, char *end, const void *addr, const char *fmt)
1435 1436
{
	unsigned long long num;
1437
	int size;
1438 1439 1440 1441

	switch (fmt[1]) {
	case 'd':
		num = *(const dma_addr_t *)addr;
1442
		size = sizeof(dma_addr_t);
1443 1444 1445 1446
		break;
	case 'p':
	default:
		num = *(const phys_addr_t *)addr;
1447
		size = sizeof(phys_addr_t);
1448 1449 1450
		break;
	}

1451
	return special_hex_number(buf, end, num, size);
1452 1453
}

1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469
static noinline_for_stack
char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
	    const char *fmt)
{
	if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk)
		return string(buf, end, NULL, spec);

	switch (fmt[1]) {
	case 'r':
		return number(buf, end, clk_get_rate(clk), spec);

	case 'n':
	default:
#ifdef CONFIG_COMMON_CLK
		return string(buf, end, __clk_get_name(clk), spec);
#else
1470
		return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long));
1471 1472 1473 1474
#endif
	}
}

1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485
static
char *format_flags(char *buf, char *end, unsigned long flags,
					const struct trace_print_flags *names)
{
	unsigned long mask;

	for ( ; flags && names->name; names++) {
		mask = names->mask;
		if ((flags & mask) != mask)
			continue;

1486
		buf = string(buf, end, names->name, default_str_spec);
1487 1488 1489 1490 1491 1492 1493 1494 1495 1496

		flags &= ~mask;
		if (flags) {
			if (buf < end)
				*buf = '|';
			buf++;
		}
	}

	if (flags)
1497
		buf = number(buf, end, flags, default_flag_spec);
1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530

	return buf;
}

static noinline_for_stack
char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt)
{
	unsigned long flags;
	const struct trace_print_flags *names;

	switch (fmt[1]) {
	case 'p':
		flags = *(unsigned long *)flags_ptr;
		/* Remove zone id */
		flags &= (1UL << NR_PAGEFLAGS) - 1;
		names = pageflag_names;
		break;
	case 'v':
		flags = *(unsigned long *)flags_ptr;
		names = vmaflag_names;
		break;
	case 'g':
		flags = *(gfp_t *)flags_ptr;
		names = gfpflag_names;
		break;
	default:
		WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]);
		return buf;
	}

	return format_flags(buf, end, flags, names);
}

1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546
static const char *device_node_name_for_depth(const struct device_node *np, int depth)
{
	for ( ; np && depth; depth--)
		np = np->parent;

	return kbasename(np->full_name);
}

static noinline_for_stack
char *device_node_gen_full_name(const struct device_node *np, char *buf, char *end)
{
	int depth;
	const struct device_node *parent = np->parent;

	/* special case for root node */
	if (!parent)
1547
		return string(buf, end, "/", default_str_spec);
1548 1549 1550 1551 1552

	for (depth = 0; parent->parent; depth++)
		parent = parent->parent;

	for ( ; depth >= 0; depth--) {
1553
		buf = string(buf, end, "/", default_str_spec);
1554
		buf = string(buf, end, device_node_name_for_depth(np, depth),
1555
			     default_str_spec);
1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646
	}
	return buf;
}

static noinline_for_stack
char *device_node_string(char *buf, char *end, struct device_node *dn,
			 struct printf_spec spec, const char *fmt)
{
	char tbuf[sizeof("xxxx") + 1];
	const char *p;
	int ret;
	char *buf_start = buf;
	struct property *prop;
	bool has_mult, pass;
	static const struct printf_spec num_spec = {
		.flags = SMALL,
		.field_width = -1,
		.precision = -1,
		.base = 10,
	};

	struct printf_spec str_spec = spec;
	str_spec.field_width = -1;

	if (!IS_ENABLED(CONFIG_OF))
		return string(buf, end, "(!OF)", spec);

	if ((unsigned long)dn < PAGE_SIZE)
		return string(buf, end, "(null)", spec);

	/* simple case without anything any more format specifiers */
	fmt++;
	if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
		fmt = "f";

	for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
		if (pass) {
			if (buf < end)
				*buf = ':';
			buf++;
		}

		switch (*fmt) {
		case 'f':	/* full_name */
			buf = device_node_gen_full_name(dn, buf, end);
			break;
		case 'n':	/* name */
			buf = string(buf, end, dn->name, str_spec);
			break;
		case 'p':	/* phandle */
			buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
			break;
		case 'P':	/* path-spec */
			p = kbasename(of_node_full_name(dn));
			if (!p[1])
				p = "/";
			buf = string(buf, end, p, str_spec);
			break;
		case 'F':	/* flags */
			tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
			tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
			tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
			tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
			tbuf[4] = 0;
			buf = string(buf, end, tbuf, str_spec);
			break;
		case 'c':	/* major compatible string */
			ret = of_property_read_string(dn, "compatible", &p);
			if (!ret)
				buf = string(buf, end, p, str_spec);
			break;
		case 'C':	/* full compatible string */
			has_mult = false;
			of_property_for_each_string(dn, "compatible", prop, p) {
				if (has_mult)
					buf = string(buf, end, ",", str_spec);
				buf = string(buf, end, "\"", str_spec);
				buf = string(buf, end, p, str_spec);
				buf = string(buf, end, "\"", str_spec);

				has_mult = true;
			}
			break;
		default:
			break;
		}
	}

	return widen_string(buf, buf - buf_start, end, spec);
}

1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683
static bool have_filled_random_ptr_key __read_mostly;
static siphash_key_t ptr_key __read_mostly;

static void fill_random_ptr_key(struct random_ready_callback *unused)
{
	get_random_bytes(&ptr_key, sizeof(ptr_key));
	/*
	 * have_filled_random_ptr_key==true is dependent on get_random_bytes().
	 * ptr_to_id() needs to see have_filled_random_ptr_key==true
	 * after get_random_bytes() returns.
	 */
	smp_mb();
	WRITE_ONCE(have_filled_random_ptr_key, true);
}

static struct random_ready_callback random_ready = {
	.func = fill_random_ptr_key
};

static int __init initialize_ptr_random(void)
{
	int ret = add_random_ready_callback(&random_ready);

	if (!ret) {
		return 0;
	} else if (ret == -EALREADY) {
		fill_random_ptr_key(&random_ready);
		return 0;
	}

	return ret;
}
early_initcall(initialize_ptr_random);

/* Maps a pointer to a 32 bit unique identifier. */
static char *ptr_to_id(char *buf, char *end, void *ptr, struct printf_spec spec)
{
1684
	const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
1685 1686 1687
	unsigned long hashval;

	if (unlikely(!have_filled_random_ptr_key)) {
1688
		spec.field_width = 2 * sizeof(ptr);
1689
		/* string length must be less than default_width */
1690
		return string(buf, end, str, spec);
1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702
	}

#ifdef CONFIG_64BIT
	hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
	/*
	 * Mask off the first 32 bits, this makes explicit that we have
	 * modified the address (and 32 bits is plenty for a unique ID).
	 */
	hashval = hashval & 0xffffffff;
#else
	hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
#endif
1703
	return pointer_string(buf, end, (const void *)hashval, spec);
1704 1705
}

1706 1707 1708 1709 1710
/*
 * Show a '%p' thing.  A kernel extension is that the '%p' is followed
 * by an extra set of alphanumeric characters that are extended format
 * specifiers.
 *
1711 1712 1713
 * Please update scripts/checkpatch.pl when adding/removing conversion
 * characters.  (Search for "check for vsprintf extension").
 *
1714 1715
 * Right now we handle:
 *
1716 1717
 * - 'F' For symbolic function descriptor pointers with offset
 * - 'f' For simple symbolic function names without offset
1718 1719
 * - 'S' For symbolic direct pointers with offset
 * - 's' For symbolic direct pointers without offset
1720
 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1721
 * - 'B' For backtraced symbolic direct pointers with offset
1722 1723
 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1724 1725 1726 1727
 * - 'b[l]' For a bitmap, the number of bits is determined by the field
 *       width which must be explicitly specified either as part of the
 *       format string '%32b[l]' or through '%*b[l]', [l] selects
 *       range-list format instead of hex format
1728 1729
 * - 'M' For a 6-byte MAC address, it prints the address in the
 *       usual colon-separated hex notation
1730
 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1731
 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1732
 *       with a dash-separated hex notation
1733
 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1734 1735 1736
 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
 *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
 *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
1737 1738 1739
 *       [S][pfs]
 *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
 *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1740 1741 1742
 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
 *       IPv6 omits the colons (01020304...0f)
 *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1743 1744 1745 1746 1747
 *       [S][pfs]
 *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
 *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
 * - 'I[6S]c' for IPv6 addresses printed as specified by
1748
 *       http://tools.ietf.org/html/rfc5952
1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759
 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
 *                of the following flags (see string_escape_mem() for the
 *                details):
 *                  a - ESCAPE_ANY
 *                  c - ESCAPE_SPECIAL
 *                  h - ESCAPE_HEX
 *                  n - ESCAPE_NULL
 *                  o - ESCAPE_OCTAL
 *                  p - ESCAPE_NP
 *                  s - ESCAPE_SPACE
 *                By default ESCAPE_ANY_NP is used.
1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770
 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
 *       "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
 *       Options for %pU are:
 *         b big endian lower case hex (default)
 *         B big endian UPPER case hex
 *         l little endian lower case hex
 *         L little endian UPPER case hex
 *           big endian output byte order is:
 *             [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
 *           little endian output byte order is:
 *             [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1771 1772 1773 1774 1775
 * - 'V' For a struct va_format which contains a format string * and va_list *,
 *       call vsnprintf(->format, *->va_list).
 *       Implements a "recursive vsnprintf".
 *       Do not use this feature without some mechanism to verify the
 *       correctness of the format string and va_list arguments.
1776
 * - 'K' For a kernel pointer that should be hidden from unprivileged users
1777
 * - 'NF' For a netdev_features_t
1778 1779 1780 1781 1782 1783 1784
 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
 *            a certain separator (' ' by default):
 *              C colon
 *              D dash
 *              N no separator
 *            The maximum supported length is 64 bytes of the input. Consider
 *            to use print_hex_dump() for the larger input.
1785 1786
 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
 *           (default assumed to be phys_addr_t, passed by reference)
1787 1788
 * - 'd[234]' For a dentry name (optionally 2-4 last components)
 * - 'D[234]' Same as 'd' but for a struct file
1789
 * - 'g' For block_device name (gendisk + partition number)
1790 1791 1792 1793 1794
 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
 *       (legacy clock framework) of the clock
 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
 *        (legacy clock framework) of the clock
 * - 'Cr' For a clock, it prints the current rate of the clock
1795 1796 1797 1798 1799
 * - 'G' For flags to be printed as a collection of symbolic strings that would
 *       construct the specific value. Supported flags given by option:
 *       p page flags (see struct page) given as pointer to unsigned long
 *       g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
 *       v vma flags (VM_*) given as pointer to unsigned long
1800 1801 1802 1803 1804 1805 1806 1807 1808 1809
 * - 'O' For a kobject based struct. Must be one of the following:
 *       - 'OF[fnpPcCF]'  For a device tree object
 *                        Without any optional arguments prints the full_name
 *                        f device node full_name
 *                        n device node name
 *                        p device node phandle
 *                        P device node path spec (name + @unit)
 *                        F device node flags
 *                        c major compatible string
 *                        C full compatible string
1810
 *
1811 1812
 * - 'x' For printing the address. Equivalent to "%lx".
 *
1813 1814
 * ** When making changes please also update:
 *	Documentation/core-api/printk-formats.rst
1815
 *
1816 1817 1818
 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
 * function pointers are really function descriptors, which contain a
 * pointer to the real address.
1819 1820 1821
 *
 * Note: The default behaviour (unadorned %p) is to hash the address,
 * rendering it useful as a unique identifier.
1822
 */
J
Joe Perches 已提交
1823 1824 1825
static noinline_for_stack
char *pointer(const char *fmt, char *buf, char *end, void *ptr,
	      struct printf_spec spec)
1826
{
1827
	const int default_width = 2 * sizeof(void *);
1828

1829
	if (!ptr && *fmt != 'K' && *fmt != 'x') {
1830 1831 1832 1833 1834
		/*
		 * Print (null) with the same width as a pointer so it makes
		 * tabular output look nice.
		 */
		if (spec.field_width == -1)
1835
			spec.field_width = default_width;
1836
		return string(buf, end, "(null)", spec);
1837
	}
1838

1839 1840
	switch (*fmt) {
	case 'F':
1841
	case 'f':
1842
	case 'S':
1843
	case 's':
1844 1845
		ptr = dereference_symbol_descriptor(ptr);
		/* Fallthrough */
1846
	case 'B':
1847
		return symbol_string(buf, end, ptr, spec, fmt);
1848
	case 'R':
1849
	case 'r':
1850
		return resource_string(buf, end, ptr, spec, fmt);
1851 1852
	case 'h':
		return hex_string(buf, end, ptr, spec, fmt);
1853 1854 1855 1856 1857 1858 1859
	case 'b':
		switch (fmt[1]) {
		case 'l':
			return bitmap_list_string(buf, end, ptr, spec, fmt);
		default:
			return bitmap_string(buf, end, ptr, spec, fmt);
		}
1860 1861
	case 'M':			/* Colon separated: 00:01:02:03:04:05 */
	case 'm':			/* Contiguous: 000102030405 */
1862 1863
					/* [mM]F (FDDI) */
					/* [mM]R (Reverse order; Bluetooth) */
1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878
		return mac_address_string(buf, end, ptr, spec, fmt);
	case 'I':			/* Formatted IP supported
					 * 4:	1.2.3.4
					 * 6:	0001:0203:...:0708
					 * 6c:	1::708 or 1::1.2.3.4
					 */
	case 'i':			/* Contiguous:
					 * 4:	001.002.003.004
					 * 6:   000102...0f
					 */
		switch (fmt[1]) {
		case '6':
			return ip6_addr_string(buf, end, ptr, spec, fmt);
		case '4':
			return ip4_addr_string(buf, end, ptr, spec, fmt);
1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893
		case 'S': {
			const union {
				struct sockaddr		raw;
				struct sockaddr_in	v4;
				struct sockaddr_in6	v6;
			} *sa = ptr;

			switch (sa->raw.sa_family) {
			case AF_INET:
				return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
			case AF_INET6:
				return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
			default:
				return string(buf, end, "(invalid address)", spec);
			}}
1894
		}
1895
		break;
1896 1897
	case 'E':
		return escaped_string(buf, end, ptr, spec, fmt);
1898 1899
	case 'U':
		return uuid_string(buf, end, ptr, spec, fmt);
1900
	case 'V':
1901 1902 1903 1904 1905 1906 1907 1908 1909
		{
			va_list va;

			va_copy(va, *((struct va_format *)ptr)->va);
			buf += vsnprintf(buf, end > buf ? end - buf : 0,
					 ((struct va_format *)ptr)->fmt, va);
			va_end(va);
			return buf;
		}
1910
	case 'K':
1911 1912
		if (!kptr_restrict)
			break;
1913
		return restricted_pointer(buf, end, ptr, spec);
1914
	case 'N':
1915
		return netdev_bits(buf, end, ptr, fmt);
1916
	case 'a':
1917
		return address_val(buf, end, ptr, fmt);
A
Al Viro 已提交
1918 1919
	case 'd':
		return dentry_name(buf, end, ptr, spec, fmt);
1920 1921
	case 'C':
		return clock(buf, end, ptr, spec, fmt);
A
Al Viro 已提交
1922 1923 1924 1925
	case 'D':
		return dentry_name(buf, end,
				   ((const struct file *)ptr)->f_path.dentry,
				   spec, fmt);
1926 1927 1928 1929 1930
#ifdef CONFIG_BLOCK
	case 'g':
		return bdev_name(buf, end, ptr, spec, fmt);
#endif

1931 1932
	case 'G':
		return flags_string(buf, end, ptr, fmt);
1933 1934 1935 1936 1937
	case 'O':
		switch (fmt[1]) {
		case 'F':
			return device_node_string(buf, end, ptr, spec, fmt + 1);
		}
1938 1939
	case 'x':
		return pointer_string(buf, end, ptr, spec);
1940 1941
	}

1942 1943
	/* default is to _not_ leak addresses, hash before printing */
	return ptr_to_id(buf, end, ptr, spec);
1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955
}

/*
 * Helper function to decode printf style format.
 * Each call decode a token from the format and return the
 * number of characters read (or likely the delta where it wants
 * to go on the next call).
 * The decoded token is returned through the parameters
 *
 * 'h', 'l', or 'L' for integer fields
 * 'z' support added 23/7/1999 S.H.
 * 'z' changed to 'Z' --davidm 1/25/99
1956
 * 'Z' changed to 'z' --adobriyan 2017-01-25
1957 1958 1959 1960 1961 1962 1963 1964 1965 1966
 * 't' added for ptrdiff_t
 *
 * @fmt: the format string
 * @type of the token returned
 * @flags: various flags such as +, -, # tokens..
 * @field_width: overwritten width
 * @base: base of the number (octal, hex, ...)
 * @precision: precision of a number
 * @qualifier: qualifier of a number (long, size_t, ...)
 */
J
Joe Perches 已提交
1967 1968
static noinline_for_stack
int format_decode(const char *fmt, struct printf_spec *spec)
1969 1970
{
	const char *start = fmt;
1971
	char qualifier;
1972 1973

	/* we finished early by reading the field width */
1974
	if (spec->type == FORMAT_TYPE_WIDTH) {
1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031
		if (spec->field_width < 0) {
			spec->field_width = -spec->field_width;
			spec->flags |= LEFT;
		}
		spec->type = FORMAT_TYPE_NONE;
		goto precision;
	}

	/* we finished early by reading the precision */
	if (spec->type == FORMAT_TYPE_PRECISION) {
		if (spec->precision < 0)
			spec->precision = 0;

		spec->type = FORMAT_TYPE_NONE;
		goto qualifier;
	}

	/* By default */
	spec->type = FORMAT_TYPE_NONE;

	for (; *fmt ; ++fmt) {
		if (*fmt == '%')
			break;
	}

	/* Return the current non-format string */
	if (fmt != start || !*fmt)
		return fmt - start;

	/* Process flags */
	spec->flags = 0;

	while (1) { /* this also skips first '%' */
		bool found = true;

		++fmt;

		switch (*fmt) {
		case '-': spec->flags |= LEFT;    break;
		case '+': spec->flags |= PLUS;    break;
		case ' ': spec->flags |= SPACE;   break;
		case '#': spec->flags |= SPECIAL; break;
		case '0': spec->flags |= ZEROPAD; break;
		default:  found = false;
		}

		if (!found)
			break;
	}

	/* get field width */
	spec->field_width = -1;

	if (isdigit(*fmt))
		spec->field_width = skip_atoi(&fmt);
	else if (*fmt == '*') {
		/* it's the next argument */
2032
		spec->type = FORMAT_TYPE_WIDTH;
2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046
		return ++fmt - start;
	}

precision:
	/* get the precision */
	spec->precision = -1;
	if (*fmt == '.') {
		++fmt;
		if (isdigit(*fmt)) {
			spec->precision = skip_atoi(&fmt);
			if (spec->precision < 0)
				spec->precision = 0;
		} else if (*fmt == '*') {
			/* it's the next argument */
2047
			spec->type = FORMAT_TYPE_PRECISION;
2048 2049 2050 2051 2052 2053
			return ++fmt - start;
		}
	}

qualifier:
	/* get the conversion qualifier */
2054
	qualifier = 0;
A
Andy Shevchenko 已提交
2055
	if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2056
	    *fmt == 'z' || *fmt == 't') {
2057 2058 2059 2060
		qualifier = *fmt++;
		if (unlikely(qualifier == *fmt)) {
			if (qualifier == 'l') {
				qualifier = 'L';
2061
				++fmt;
2062 2063
			} else if (qualifier == 'h') {
				qualifier = 'H';
2064 2065
				++fmt;
			}
2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081
		}
	}

	/* default base */
	spec->base = 10;
	switch (*fmt) {
	case 'c':
		spec->type = FORMAT_TYPE_CHAR;
		return ++fmt - start;

	case 's':
		spec->type = FORMAT_TYPE_STR;
		return ++fmt - start;

	case 'p':
		spec->type = FORMAT_TYPE_PTR;
2082
		return ++fmt - start;
2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094

	case '%':
		spec->type = FORMAT_TYPE_PERCENT_CHAR;
		return ++fmt - start;

	/* integer number formats - set up the flags and "break" */
	case 'o':
		spec->base = 8;
		break;

	case 'x':
		spec->flags |= SMALL;
2095
		/* fall through */
2096 2097 2098 2099 2100 2101 2102

	case 'X':
		spec->base = 16;
		break;

	case 'd':
	case 'i':
2103
		spec->flags |= SIGN;
2104
	case 'u':
2105
		break;
2106

R
Ryan Mallon 已提交
2107 2108
	case 'n':
		/*
2109 2110 2111
		 * Since %n poses a greater security risk than
		 * utility, treat it as any other invalid or
		 * unsupported format specifier.
R
Ryan Mallon 已提交
2112 2113 2114
		 */
		/* Fall-through */

2115
	default:
2116
		WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
2117 2118
		spec->type = FORMAT_TYPE_INVALID;
		return fmt - start;
2119
	}
2120

2121
	if (qualifier == 'L')
2122
		spec->type = FORMAT_TYPE_LONG_LONG;
2123
	else if (qualifier == 'l') {
2124 2125
		BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
		spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
2126
	} else if (qualifier == 'z') {
2127
		spec->type = FORMAT_TYPE_SIZE_T;
2128
	} else if (qualifier == 't') {
2129
		spec->type = FORMAT_TYPE_PTRDIFF;
2130
	} else if (qualifier == 'H') {
2131 2132
		BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
		spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
2133
	} else if (qualifier == 'h') {
2134 2135
		BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
		spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
2136
	} else {
2137 2138
		BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
		spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
2139
	}
2140 2141

	return ++fmt - start;
2142 2143
}

2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161
static void
set_field_width(struct printf_spec *spec, int width)
{
	spec->field_width = width;
	if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
		spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
	}
}

static void
set_precision(struct printf_spec *spec, int prec)
{
	spec->precision = prec;
	if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
		spec->precision = clamp(prec, 0, PRECISION_MAX);
	}
}

L
Linus Torvalds 已提交
2162 2163 2164 2165 2166 2167 2168
/**
 * vsnprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @size: The size of the buffer, including the trailing null space
 * @fmt: The format string to use
 * @args: Arguments for the format string
 *
2169 2170 2171
 * This function generally follows C99 vsnprintf, but has some
 * extensions and a few limitations:
 *
2172 2173
 *  - ``%n`` is unsupported
 *  - ``%p*`` is handled by pointer()
2174
 *
2175
 * See pointer() or Documentation/core-api/printk-formats.rst for more
2176
 * extensive description.
2177
 *
2178
 * **Please update the documentation in both places when making changes**
2179
 *
L
Linus Torvalds 已提交
2180 2181 2182 2183
 * The return value is the number of characters which would
 * be generated for the given input, excluding the trailing
 * '\0', as per ISO C99. If you want to have the exact
 * number of characters written into @buf as return value
2184
 * (not including the trailing '\0'), use vscnprintf(). If the
L
Linus Torvalds 已提交
2185 2186 2187
 * return is greater than or equal to @size, the resulting
 * string is truncated.
 *
2188
 * If you're not already dealing with a va_list consider using snprintf().
L
Linus Torvalds 已提交
2189 2190 2191 2192
 */
int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
	unsigned long long num;
2193
	char *str, *end;
2194
	struct printf_spec spec = {0};
L
Linus Torvalds 已提交
2195

2196 2197
	/* Reject out-of-range values early.  Large positive sizes are
	   used for unknown buffer sizes. */
2198
	if (WARN_ON_ONCE(size > INT_MAX))
L
Linus Torvalds 已提交
2199 2200 2201
		return 0;

	str = buf;
2202
	end = buf + size;
L
Linus Torvalds 已提交
2203

2204 2205 2206 2207
	/* Make sure end is always >= buf */
	if (end < buf) {
		end = ((void *)-1);
		size = end - buf;
L
Linus Torvalds 已提交
2208 2209
	}

2210 2211
	while (*fmt) {
		const char *old_fmt = fmt;
2212
		int read = format_decode(fmt, &spec);
L
Linus Torvalds 已提交
2213

2214
		fmt += read;
L
Linus Torvalds 已提交
2215

2216 2217 2218 2219 2220 2221 2222
		switch (spec.type) {
		case FORMAT_TYPE_NONE: {
			int copy = read;
			if (str < end) {
				if (copy > end - str)
					copy = end - str;
				memcpy(str, old_fmt, copy);
L
Linus Torvalds 已提交
2223
			}
2224 2225
			str += read;
			break;
L
Linus Torvalds 已提交
2226 2227
		}

2228
		case FORMAT_TYPE_WIDTH:
2229
			set_field_width(&spec, va_arg(args, int));
2230
			break;
L
Linus Torvalds 已提交
2231

2232
		case FORMAT_TYPE_PRECISION:
2233
			set_precision(&spec, va_arg(args, int));
2234
			break;
L
Linus Torvalds 已提交
2235

2236 2237 2238
		case FORMAT_TYPE_CHAR: {
			char c;

2239 2240
			if (!(spec.flags & LEFT)) {
				while (--spec.field_width > 0) {
2241
					if (str < end)
L
Linus Torvalds 已提交
2242 2243 2244
						*str = ' ';
					++str;

2245 2246 2247 2248 2249 2250 2251
				}
			}
			c = (unsigned char) va_arg(args, int);
			if (str < end)
				*str = c;
			++str;
			while (--spec.field_width > 0) {
2252
				if (str < end)
2253
					*str = ' ';
L
Linus Torvalds 已提交
2254
				++str;
2255 2256
			}
			break;
2257
		}
L
Linus Torvalds 已提交
2258

2259 2260 2261
		case FORMAT_TYPE_STR:
			str = string(str, end, va_arg(args, char *), spec);
			break;
L
Linus Torvalds 已提交
2262

2263
		case FORMAT_TYPE_PTR:
2264
			str = pointer(fmt, str, end, va_arg(args, void *),
2265 2266 2267 2268
				      spec);
			while (isalnum(*fmt))
				fmt++;
			break;
L
Linus Torvalds 已提交
2269

2270 2271 2272 2273 2274
		case FORMAT_TYPE_PERCENT_CHAR:
			if (str < end)
				*str = '%';
			++str;
			break;
L
Linus Torvalds 已提交
2275

2276
		case FORMAT_TYPE_INVALID:
2277 2278 2279 2280 2281 2282 2283 2284 2285
			/*
			 * Presumably the arguments passed gcc's type
			 * checking, but there is no safe or sane way
			 * for us to continue parsing the format and
			 * fetching from the va_list; the remaining
			 * specifiers and arguments would be out of
			 * sync.
			 */
			goto out;
2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298

		default:
			switch (spec.type) {
			case FORMAT_TYPE_LONG_LONG:
				num = va_arg(args, long long);
				break;
			case FORMAT_TYPE_ULONG:
				num = va_arg(args, unsigned long);
				break;
			case FORMAT_TYPE_LONG:
				num = va_arg(args, long);
				break;
			case FORMAT_TYPE_SIZE_T:
2299 2300 2301 2302
				if (spec.flags & SIGN)
					num = va_arg(args, ssize_t);
				else
					num = va_arg(args, size_t);
2303 2304 2305 2306
				break;
			case FORMAT_TYPE_PTRDIFF:
				num = va_arg(args, ptrdiff_t);
				break;
2307 2308 2309 2310 2311 2312
			case FORMAT_TYPE_UBYTE:
				num = (unsigned char) va_arg(args, int);
				break;
			case FORMAT_TYPE_BYTE:
				num = (signed char) va_arg(args, int);
				break;
2313 2314 2315 2316 2317 2318
			case FORMAT_TYPE_USHORT:
				num = (unsigned short) va_arg(args, int);
				break;
			case FORMAT_TYPE_SHORT:
				num = (short) va_arg(args, int);
				break;
2319 2320
			case FORMAT_TYPE_INT:
				num = (int) va_arg(args, int);
2321 2322 2323 2324 2325 2326
				break;
			default:
				num = va_arg(args, unsigned int);
			}

			str = number(str, end, num, spec);
L
Linus Torvalds 已提交
2327 2328
		}
	}
2329

2330
out:
2331 2332 2333 2334
	if (size > 0) {
		if (str < end)
			*str = '\0';
		else
L
Linus Torvalds 已提交
2335
			end[-1] = '\0';
2336
	}
2337

2338
	/* the trailing null byte doesn't count towards the total */
L
Linus Torvalds 已提交
2339
	return str-buf;
2340

L
Linus Torvalds 已提交
2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351
}
EXPORT_SYMBOL(vsnprintf);

/**
 * vscnprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @size: The size of the buffer, including the trailing null space
 * @fmt: The format string to use
 * @args: Arguments for the format string
 *
 * The return value is the number of characters which have been written into
2352
 * the @buf not including the trailing '\0'. If @size is == 0 the function
L
Linus Torvalds 已提交
2353 2354
 * returns 0.
 *
2355
 * If you're not already dealing with a va_list consider using scnprintf().
2356 2357
 *
 * See the vsnprintf() documentation for format string extensions over C99.
L
Linus Torvalds 已提交
2358 2359 2360 2361 2362
 */
int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
	int i;

2363 2364
	i = vsnprintf(buf, size, fmt, args);

2365 2366 2367 2368 2369
	if (likely(i < size))
		return i;
	if (size != 0)
		return size - 1;
	return 0;
L
Linus Torvalds 已提交
2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383
}
EXPORT_SYMBOL(vscnprintf);

/**
 * snprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @size: The size of the buffer, including the trailing null space
 * @fmt: The format string to use
 * @...: Arguments for the format string
 *
 * The return value is the number of characters which would be
 * generated for the given input, excluding the trailing null,
 * as per ISO C99.  If the return is greater than or equal to
 * @size, the resulting string is truncated.
2384 2385
 *
 * See the vsnprintf() documentation for format string extensions over C99.
L
Linus Torvalds 已提交
2386
 */
2387
int snprintf(char *buf, size_t size, const char *fmt, ...)
L
Linus Torvalds 已提交
2388 2389 2390 2391 2392
{
	va_list args;
	int i;

	va_start(args, fmt);
2393
	i = vsnprintf(buf, size, fmt, args);
L
Linus Torvalds 已提交
2394
	va_end(args);
2395

L
Linus Torvalds 已提交
2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407
	return i;
}
EXPORT_SYMBOL(snprintf);

/**
 * scnprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @size: The size of the buffer, including the trailing null space
 * @fmt: The format string to use
 * @...: Arguments for the format string
 *
 * The return value is the number of characters written into @buf not including
2408
 * the trailing '\0'. If @size is == 0 the function returns 0.
L
Linus Torvalds 已提交
2409 2410
 */

2411
int scnprintf(char *buf, size_t size, const char *fmt, ...)
L
Linus Torvalds 已提交
2412 2413 2414 2415 2416
{
	va_list args;
	int i;

	va_start(args, fmt);
2417
	i = vscnprintf(buf, size, fmt, args);
L
Linus Torvalds 已提交
2418
	va_end(args);
2419

2420
	return i;
L
Linus Torvalds 已提交
2421 2422 2423 2424 2425 2426 2427 2428 2429 2430
}
EXPORT_SYMBOL(scnprintf);

/**
 * vsprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @fmt: The format string to use
 * @args: Arguments for the format string
 *
 * The function returns the number of characters written
2431
 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
L
Linus Torvalds 已提交
2432 2433
 * buffer overflows.
 *
2434
 * If you're not already dealing with a va_list consider using sprintf().
2435 2436
 *
 * See the vsnprintf() documentation for format string extensions over C99.
L
Linus Torvalds 已提交
2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450
 */
int vsprintf(char *buf, const char *fmt, va_list args)
{
	return vsnprintf(buf, INT_MAX, fmt, args);
}
EXPORT_SYMBOL(vsprintf);

/**
 * sprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @fmt: The format string to use
 * @...: Arguments for the format string
 *
 * The function returns the number of characters written
2451
 * into @buf. Use snprintf() or scnprintf() in order to avoid
L
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2452
 * buffer overflows.
2453 2454
 *
 * See the vsnprintf() documentation for format string extensions over C99.
L
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2455
 */
2456
int sprintf(char *buf, const char *fmt, ...)
L
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2457 2458 2459 2460 2461
{
	va_list args;
	int i;

	va_start(args, fmt);
2462
	i = vsnprintf(buf, INT_MAX, fmt, args);
L
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2463
	va_end(args);
2464

L
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2465 2466 2467 2468
	return i;
}
EXPORT_SYMBOL(sprintf);

L
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2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483
#ifdef CONFIG_BINARY_PRINTF
/*
 * bprintf service:
 * vbin_printf() - VA arguments to binary data
 * bstr_printf() - Binary data to text string
 */

/**
 * vbin_printf - Parse a format string and place args' binary value in a buffer
 * @bin_buf: The buffer to place args' binary value
 * @size: The size of the buffer(by words(32bits), not characters)
 * @fmt: The format string to use
 * @args: Arguments for the format string
 *
 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2484
 * is skipped.
L
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2485 2486 2487 2488 2489 2490 2491 2492 2493 2494
 *
 * The return value is the number of words(32bits) which would be generated for
 * the given input.
 *
 * NOTE:
 * If the return value is greater than @size, the resulting bin_buf is NOT
 * valid for bstr_printf().
 */
int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
{
2495
	struct printf_spec spec = {0};
L
Lai Jiangshan 已提交
2496
	char *str, *end;
2497
	int width;
L
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2498 2499 2500 2501 2502

	str = (char *)bin_buf;
	end = (char *)(bin_buf + size);

#define save_arg(type)							\
2503 2504
({									\
	unsigned long long value;					\
L
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2505
	if (sizeof(type) == 8) {					\
2506
		unsigned long long val8;				\
L
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2507
		str = PTR_ALIGN(str, sizeof(u32));			\
2508
		val8 = va_arg(args, unsigned long long);		\
L
Lai Jiangshan 已提交
2509
		if (str + sizeof(type) <= end) {			\
2510 2511
			*(u32 *)str = *(u32 *)&val8;			\
			*(u32 *)(str + 4) = *((u32 *)&val8 + 1);	\
L
Lai Jiangshan 已提交
2512
		}							\
2513
		value = val8;						\
L
Lai Jiangshan 已提交
2514
	} else {							\
2515
		unsigned int val4;					\
L
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2516
		str = PTR_ALIGN(str, sizeof(type));			\
2517
		val4 = va_arg(args, int);				\
L
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2518
		if (str + sizeof(type) <= end)				\
2519 2520
			*(typeof(type) *)str = (type)(long)val4;	\
		value = (unsigned long long)val4;			\
L
Lai Jiangshan 已提交
2521 2522
	}								\
	str += sizeof(type);						\
2523 2524
	value;								\
})
L
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2525

2526
	while (*fmt) {
2527
		int read = format_decode(fmt, &spec);
L
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2528

2529
		fmt += read;
L
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2530

2531 2532
		switch (spec.type) {
		case FORMAT_TYPE_NONE:
2533
		case FORMAT_TYPE_PERCENT_CHAR:
2534
			break;
2535 2536
		case FORMAT_TYPE_INVALID:
			goto out;
2537

2538
		case FORMAT_TYPE_WIDTH:
2539
		case FORMAT_TYPE_PRECISION:
2540 2541 2542 2543
			width = (int)save_arg(int);
			/* Pointers may require the width */
			if (*fmt == 'p')
				set_field_width(&spec, width);
2544 2545 2546
			break;

		case FORMAT_TYPE_CHAR:
L
Lai Jiangshan 已提交
2547
			save_arg(char);
2548 2549 2550
			break;

		case FORMAT_TYPE_STR: {
L
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2551 2552
			const char *save_str = va_arg(args, char *);
			size_t len;
2553

L
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2554 2555
			if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
					|| (unsigned long)save_str < PAGE_SIZE)
2556
				save_str = "(null)";
2557 2558 2559 2560
			len = strlen(save_str) + 1;
			if (str + len < end)
				memcpy(str, save_str, len);
			str += len;
2561
			break;
L
Lai Jiangshan 已提交
2562
		}
2563 2564

		case FORMAT_TYPE_PTR:
2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585
			/* Dereferenced pointers must be done now */
			switch (*fmt) {
			/* Dereference of functions is still OK */
			case 'S':
			case 's':
			case 'F':
			case 'f':
				save_arg(void *);
				break;
			default:
				if (!isalnum(*fmt)) {
					save_arg(void *);
					break;
				}
				str = pointer(fmt, str, end, va_arg(args, void *),
					      spec);
				if (str + 1 < end)
					*str++ = '\0';
				else
					end[-1] = '\0'; /* Must be nul terminated */
			}
L
Lai Jiangshan 已提交
2586
			/* skip all alphanumeric pointer suffixes */
2587
			while (isalnum(*fmt))
L
Lai Jiangshan 已提交
2588
				fmt++;
2589 2590 2591 2592 2593 2594
			break;

		default:
			switch (spec.type) {

			case FORMAT_TYPE_LONG_LONG:
L
Lai Jiangshan 已提交
2595
				save_arg(long long);
2596 2597 2598
				break;
			case FORMAT_TYPE_ULONG:
			case FORMAT_TYPE_LONG:
L
Lai Jiangshan 已提交
2599
				save_arg(unsigned long);
2600 2601
				break;
			case FORMAT_TYPE_SIZE_T:
L
Lai Jiangshan 已提交
2602
				save_arg(size_t);
2603 2604
				break;
			case FORMAT_TYPE_PTRDIFF:
L
Lai Jiangshan 已提交
2605
				save_arg(ptrdiff_t);
2606
				break;
2607 2608 2609 2610
			case FORMAT_TYPE_UBYTE:
			case FORMAT_TYPE_BYTE:
				save_arg(char);
				break;
2611 2612
			case FORMAT_TYPE_USHORT:
			case FORMAT_TYPE_SHORT:
L
Lai Jiangshan 已提交
2613
				save_arg(short);
2614 2615
				break;
			default:
L
Lai Jiangshan 已提交
2616
				save_arg(int);
2617
			}
L
Lai Jiangshan 已提交
2618 2619
		}
	}
2620

2621
out:
2622
	return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2623
#undef save_arg
L
Lai Jiangshan 已提交
2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638
}
EXPORT_SYMBOL_GPL(vbin_printf);

/**
 * bstr_printf - Format a string from binary arguments and place it in a buffer
 * @buf: The buffer to place the result into
 * @size: The size of the buffer, including the trailing null space
 * @fmt: The format string to use
 * @bin_buf: Binary arguments for the format string
 *
 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
 * a binary buffer that generated by vbin_printf.
 *
 * The format follows C99 vsnprintf, but has some extensions:
2639
 *  see vsnprintf comment for details.
L
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2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650
 *
 * The return value is the number of characters which would
 * be generated for the given input, excluding the trailing
 * '\0', as per ISO C99. If you want to have the exact
 * number of characters written into @buf as return value
 * (not including the trailing '\0'), use vscnprintf(). If the
 * return is greater than or equal to @size, the resulting
 * string is truncated.
 */
int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
{
2651
	struct printf_spec spec = {0};
2652 2653
	char *str, *end;
	const char *args = (const char *)bin_buf;
L
Lai Jiangshan 已提交
2654

2655
	if (WARN_ON_ONCE(size > INT_MAX))
L
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2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681
		return 0;

	str = buf;
	end = buf + size;

#define get_arg(type)							\
({									\
	typeof(type) value;						\
	if (sizeof(type) == 8) {					\
		args = PTR_ALIGN(args, sizeof(u32));			\
		*(u32 *)&value = *(u32 *)args;				\
		*((u32 *)&value + 1) = *(u32 *)(args + 4);		\
	} else {							\
		args = PTR_ALIGN(args, sizeof(type));			\
		value = *(typeof(type) *)args;				\
	}								\
	args += sizeof(type);						\
	value;								\
})

	/* Make sure end is always >= buf */
	if (end < buf) {
		end = ((void *)-1);
		size = end - buf;
	}

2682 2683
	while (*fmt) {
		const char *old_fmt = fmt;
2684
		int read = format_decode(fmt, &spec);
L
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2685

2686
		fmt += read;
L
Lai Jiangshan 已提交
2687

2688 2689 2690 2691 2692 2693 2694
		switch (spec.type) {
		case FORMAT_TYPE_NONE: {
			int copy = read;
			if (str < end) {
				if (copy > end - str)
					copy = end - str;
				memcpy(str, old_fmt, copy);
L
Lai Jiangshan 已提交
2695
			}
2696 2697
			str += read;
			break;
L
Lai Jiangshan 已提交
2698 2699
		}

2700
		case FORMAT_TYPE_WIDTH:
2701
			set_field_width(&spec, get_arg(int));
2702
			break;
L
Lai Jiangshan 已提交
2703

2704
		case FORMAT_TYPE_PRECISION:
2705
			set_precision(&spec, get_arg(int));
2706
			break;
L
Lai Jiangshan 已提交
2707

2708 2709 2710
		case FORMAT_TYPE_CHAR: {
			char c;

2711 2712
			if (!(spec.flags & LEFT)) {
				while (--spec.field_width > 0) {
L
Lai Jiangshan 已提交
2713 2714 2715 2716 2717 2718 2719 2720 2721
					if (str < end)
						*str = ' ';
					++str;
				}
			}
			c = (unsigned char) get_arg(char);
			if (str < end)
				*str = c;
			++str;
2722
			while (--spec.field_width > 0) {
L
Lai Jiangshan 已提交
2723 2724 2725 2726
				if (str < end)
					*str = ' ';
				++str;
			}
2727
			break;
2728
		}
L
Lai Jiangshan 已提交
2729

2730
		case FORMAT_TYPE_STR: {
L
Lai Jiangshan 已提交
2731
			const char *str_arg = args;
2732
			args += strlen(str_arg) + 1;
2733 2734
			str = string(str, end, (char *)str_arg, spec);
			break;
L
Lai Jiangshan 已提交
2735 2736
		}

2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765
		case FORMAT_TYPE_PTR: {
			bool process = false;
			int copy, len;
			/* Non function dereferences were already done */
			switch (*fmt) {
			case 'S':
			case 's':
			case 'F':
			case 'f':
				process = true;
				break;
			default:
				if (!isalnum(*fmt)) {
					process = true;
					break;
				}
				/* Pointer dereference was already processed */
				if (str < end) {
					len = copy = strlen(args);
					if (copy > end - str)
						copy = end - str;
					memcpy(str, args, copy);
					str += len;
					args += len;
				}
			}
			if (process)
				str = pointer(fmt, str, end, get_arg(void *), spec);

2766
			while (isalnum(*fmt))
L
Lai Jiangshan 已提交
2767
				fmt++;
2768
			break;
2769
		}
L
Lai Jiangshan 已提交
2770

2771
		case FORMAT_TYPE_PERCENT_CHAR:
L
Lai Jiangshan 已提交
2772 2773 2774
			if (str < end)
				*str = '%';
			++str;
2775 2776
			break;

2777 2778 2779
		case FORMAT_TYPE_INVALID:
			goto out;

2780 2781 2782
		default: {
			unsigned long long num;

2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797
			switch (spec.type) {

			case FORMAT_TYPE_LONG_LONG:
				num = get_arg(long long);
				break;
			case FORMAT_TYPE_ULONG:
			case FORMAT_TYPE_LONG:
				num = get_arg(unsigned long);
				break;
			case FORMAT_TYPE_SIZE_T:
				num = get_arg(size_t);
				break;
			case FORMAT_TYPE_PTRDIFF:
				num = get_arg(ptrdiff_t);
				break;
2798 2799 2800 2801 2802 2803
			case FORMAT_TYPE_UBYTE:
				num = get_arg(unsigned char);
				break;
			case FORMAT_TYPE_BYTE:
				num = get_arg(signed char);
				break;
2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816 2817
			case FORMAT_TYPE_USHORT:
				num = get_arg(unsigned short);
				break;
			case FORMAT_TYPE_SHORT:
				num = get_arg(short);
				break;
			case FORMAT_TYPE_UINT:
				num = get_arg(unsigned int);
				break;
			default:
				num = get_arg(int);
			}

			str = number(str, end, num, spec);
2818 2819 2820
		} /* default: */
		} /* switch(spec.type) */
	} /* while(*fmt) */
2821

2822
out:
L
Lai Jiangshan 已提交
2823 2824 2825 2826 2827 2828
	if (size > 0) {
		if (str < end)
			*str = '\0';
		else
			end[-1] = '\0';
	}
2829

L
Lai Jiangshan 已提交
2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854
#undef get_arg

	/* the trailing null byte doesn't count towards the total */
	return str - buf;
}
EXPORT_SYMBOL_GPL(bstr_printf);

/**
 * bprintf - Parse a format string and place args' binary value in a buffer
 * @bin_buf: The buffer to place args' binary value
 * @size: The size of the buffer(by words(32bits), not characters)
 * @fmt: The format string to use
 * @...: Arguments for the format string
 *
 * The function returns the number of words(u32) written
 * into @bin_buf.
 */
int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
{
	va_list args;
	int ret;

	va_start(args, fmt);
	ret = vbin_printf(bin_buf, size, fmt, args);
	va_end(args);
2855

L
Lai Jiangshan 已提交
2856 2857 2858 2859 2860 2861
	return ret;
}
EXPORT_SYMBOL_GPL(bprintf);

#endif /* CONFIG_BINARY_PRINTF */

L
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2862 2863 2864 2865 2866 2867
/**
 * vsscanf - Unformat a buffer into a list of arguments
 * @buf:	input buffer
 * @fmt:	format of buffer
 * @args:	arguments
 */
2868
int vsscanf(const char *buf, const char *fmt, va_list args)
L
Linus Torvalds 已提交
2869 2870 2871 2872 2873
{
	const char *str = buf;
	char *next;
	char digit;
	int num = 0;
2874
	u8 qualifier;
2875 2876 2877 2878 2879
	unsigned int base;
	union {
		long long s;
		unsigned long long u;
	} val;
2880
	s16 field_width;
2881
	bool is_sign;
L
Linus Torvalds 已提交
2882

2883
	while (*fmt) {
L
Linus Torvalds 已提交
2884 2885 2886 2887 2888
		/* skip any white space in format */
		/* white space in format matchs any amount of
		 * white space, including none, in the input.
		 */
		if (isspace(*fmt)) {
2889 2890
			fmt = skip_spaces(++fmt);
			str = skip_spaces(str);
L
Linus Torvalds 已提交
2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902
		}

		/* anything that is not a conversion must match exactly */
		if (*fmt != '%' && *fmt) {
			if (*fmt++ != *str++)
				break;
			continue;
		}

		if (!*fmt)
			break;
		++fmt;
2903

L
Linus Torvalds 已提交
2904 2905 2906 2907
		/* skip this conversion.
		 * advance both strings to next white space
		 */
		if (*fmt == '*') {
2908 2909
			if (!*str)
				break;
2910 2911 2912 2913
			while (!isspace(*fmt) && *fmt != '%' && *fmt) {
				/* '%*[' not yet supported, invalid format */
				if (*fmt == '[')
					return num;
L
Linus Torvalds 已提交
2914
				fmt++;
2915
			}
L
Linus Torvalds 已提交
2916 2917 2918 2919 2920 2921 2922
			while (!isspace(*str) && *str)
				str++;
			continue;
		}

		/* get field width */
		field_width = -1;
2923
		if (isdigit(*fmt)) {
L
Linus Torvalds 已提交
2924
			field_width = skip_atoi(&fmt);
2925 2926 2927
			if (field_width <= 0)
				break;
		}
L
Linus Torvalds 已提交
2928 2929 2930

		/* get conversion qualifier */
		qualifier = -1;
A
Andy Shevchenko 已提交
2931
		if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2932
		    *fmt == 'z') {
L
Linus Torvalds 已提交
2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944
			qualifier = *fmt++;
			if (unlikely(qualifier == *fmt)) {
				if (qualifier == 'h') {
					qualifier = 'H';
					fmt++;
				} else if (qualifier == 'l') {
					qualifier = 'L';
					fmt++;
				}
			}
		}

2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955
		if (!*fmt)
			break;

		if (*fmt == 'n') {
			/* return number of characters read so far */
			*va_arg(args, int *) = str - buf;
			++fmt;
			continue;
		}

		if (!*str)
L
Linus Torvalds 已提交
2956 2957
			break;

2958
		base = 10;
2959
		is_sign = false;
2960

2961
		switch (*fmt++) {
L
Linus Torvalds 已提交
2962 2963
		case 'c':
		{
2964
			char *s = (char *)va_arg(args, char*);
L
Linus Torvalds 已提交
2965 2966 2967 2968 2969 2970 2971 2972 2973 2974
			if (field_width == -1)
				field_width = 1;
			do {
				*s++ = *str++;
			} while (--field_width > 0 && *str);
			num++;
		}
		continue;
		case 's':
		{
2975 2976
			char *s = (char *)va_arg(args, char *);
			if (field_width == -1)
2977
				field_width = SHRT_MAX;
L
Linus Torvalds 已提交
2978
			/* first, skip leading white space in buffer */
2979
			str = skip_spaces(str);
L
Linus Torvalds 已提交
2980 2981

			/* now copy until next white space */
2982
			while (*str && !isspace(*str) && field_width--)
L
Linus Torvalds 已提交
2983 2984 2985 2986 2987
				*s++ = *str++;
			*s = '\0';
			num++;
		}
		continue;
2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040
		/*
		 * Warning: This implementation of the '[' conversion specifier
		 * deviates from its glibc counterpart in the following ways:
		 * (1) It does NOT support ranges i.e. '-' is NOT a special
		 *     character
		 * (2) It cannot match the closing bracket ']' itself
		 * (3) A field width is required
		 * (4) '%*[' (discard matching input) is currently not supported
		 *
		 * Example usage:
		 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
		 *		buf1, buf2, buf3);
		 * if (ret < 3)
		 *    // etc..
		 */
		case '[':
		{
			char *s = (char *)va_arg(args, char *);
			DECLARE_BITMAP(set, 256) = {0};
			unsigned int len = 0;
			bool negate = (*fmt == '^');

			/* field width is required */
			if (field_width == -1)
				return num;

			if (negate)
				++fmt;

			for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
				set_bit((u8)*fmt, set);

			/* no ']' or no character set found */
			if (!*fmt || !len)
				return num;
			++fmt;

			if (negate) {
				bitmap_complement(set, set, 256);
				/* exclude null '\0' byte */
				clear_bit(0, set);
			}

			/* match must be non-empty */
			if (!test_bit((u8)*str, set))
				return num;

			while (test_bit((u8)*str, set) && field_width--)
				*s++ = *str++;
			*s = '\0';
			++num;
		}
		continue;
L
Linus Torvalds 已提交
3041 3042 3043 3044 3045 3046 3047 3048
		case 'o':
			base = 8;
			break;
		case 'x':
		case 'X':
			base = 16;
			break;
		case 'i':
3049
			base = 0;
3050
			/* fall through */
L
Linus Torvalds 已提交
3051
		case 'd':
3052
			is_sign = true;
3053
			/* fall through */
L
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3054 3055 3056 3057
		case 'u':
			break;
		case '%':
			/* looking for '%' in str */
3058
			if (*str++ != '%')
L
Linus Torvalds 已提交
3059 3060 3061 3062 3063 3064 3065 3066 3067 3068
				return num;
			continue;
		default:
			/* invalid format; stop here */
			return num;
		}

		/* have some sort of integer conversion.
		 * first, skip white space in buffer.
		 */
3069
		str = skip_spaces(str);
L
Linus Torvalds 已提交
3070 3071 3072 3073 3074 3075

		digit = *str;
		if (is_sign && digit == '-')
			digit = *(str + 1);

		if (!digit
3076 3077 3078 3079 3080
		    || (base == 16 && !isxdigit(digit))
		    || (base == 10 && !isdigit(digit))
		    || (base == 8 && (!isdigit(digit) || digit > '7'))
		    || (base == 0 && !isdigit(digit)))
			break;
L
Linus Torvalds 已提交
3081

3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102
		if (is_sign)
			val.s = qualifier != 'L' ?
				simple_strtol(str, &next, base) :
				simple_strtoll(str, &next, base);
		else
			val.u = qualifier != 'L' ?
				simple_strtoul(str, &next, base) :
				simple_strtoull(str, &next, base);

		if (field_width > 0 && next - str > field_width) {
			if (base == 0)
				_parse_integer_fixup_radix(str, &base);
			while (next - str > field_width) {
				if (is_sign)
					val.s = div_s64(val.s, base);
				else
					val.u = div_u64(val.u, base);
				--next;
			}
		}

3103
		switch (qualifier) {
L
Linus Torvalds 已提交
3104
		case 'H':	/* that's 'hh' in format */
3105 3106 3107 3108
			if (is_sign)
				*va_arg(args, signed char *) = val.s;
			else
				*va_arg(args, unsigned char *) = val.u;
L
Linus Torvalds 已提交
3109 3110
			break;
		case 'h':
3111 3112 3113 3114
			if (is_sign)
				*va_arg(args, short *) = val.s;
			else
				*va_arg(args, unsigned short *) = val.u;
L
Linus Torvalds 已提交
3115 3116
			break;
		case 'l':
3117 3118 3119 3120
			if (is_sign)
				*va_arg(args, long *) = val.s;
			else
				*va_arg(args, unsigned long *) = val.u;
L
Linus Torvalds 已提交
3121 3122
			break;
		case 'L':
3123 3124 3125 3126
			if (is_sign)
				*va_arg(args, long long *) = val.s;
			else
				*va_arg(args, unsigned long long *) = val.u;
L
Linus Torvalds 已提交
3127 3128
			break;
		case 'z':
3129 3130
			*va_arg(args, size_t *) = val.u;
			break;
L
Linus Torvalds 已提交
3131
		default:
3132 3133 3134 3135
			if (is_sign)
				*va_arg(args, int *) = val.s;
			else
				*va_arg(args, unsigned int *) = val.u;
L
Linus Torvalds 已提交
3136 3137 3138 3139 3140 3141 3142 3143
			break;
		}
		num++;

		if (!next)
			break;
		str = next;
	}
3144

L
Linus Torvalds 已提交
3145 3146 3147 3148 3149 3150 3151 3152 3153 3154
	return num;
}
EXPORT_SYMBOL(vsscanf);

/**
 * sscanf - Unformat a buffer into a list of arguments
 * @buf:	input buffer
 * @fmt:	formatting of buffer
 * @...:	resulting arguments
 */
3155
int sscanf(const char *buf, const char *fmt, ...)
L
Linus Torvalds 已提交
3156 3157 3158 3159
{
	va_list args;
	int i;

3160 3161
	va_start(args, fmt);
	i = vsscanf(buf, fmt, args);
L
Linus Torvalds 已提交
3162
	va_end(args);
3163

L
Linus Torvalds 已提交
3164 3165 3166
	return i;
}
EXPORT_SYMBOL(sscanf);